Some conventional snowmobiles are equipped with a front suspension system utilizing trailing arms. A trailing arm front suspension system consists of two radius rods and two trailing arms connecting the ski legs to the snowmobile frame. The two radius rods extend substantially perpendicular to the longitudinal axis of the snowmobile while the trailing arms extend rearwardly substantially parallel to the longitudinal axis of the snowmobile. The front end of the trailing arm is connected to the ski leg, and the rear end of the trailing arm is pivotally connected to the snowmobile frame. In operation, the vertical movement of the ski leg follows the arc defined by the trailing arm. A trailing arm suspension geometry generates a forward motion of the skis when the suspension is compressed such that the skis have to slide forward for the suspension to be compressed. Because the skis move forward when absorbing shocks or landing from a jump, they work in the opposite direction of energy absorption. Therefore more stress is added on the front suspension components and on the frame of the snowmobile when the suspension is compressed. Furthermore, the impact forces felt by the driver of the snowmobile is greater. The trailing arm suspension geometry thus requires heavy springs, reinforced suspension arms and a reinforced frame to handle these extreme conditions thereby increasing weight and cost of the snowmobile. A trailing arm suspension geometry also generates an increase in caster angle such that more effort is required by the driver to turn the skis of the snowmobile when the suspension is compressed.
Other conventional snowmobiles are equipped with a front suspension having a double A-arm suspension geometry, also known as double wishbone suspension geometry. These types of systems have proven to be better able to handle extreme riding conditions and eliminated some of the major drawbacks of the previous described trailing arm suspension geometry because the skis do not necessarily move forward when the front suspension is compressed. However, conventional double A-arm suspension geometry still require more efforts from the driver to turn the skis of the snowmobile when the suspension is compressed.
Thus, there is a need for a snowmobile front suspension that alleviates some of the drawbacks of conventional front suspension systems and preferably reduces the steering effort required when the suspension is compressed.